PLANTATION, Fla., March 17 - Viragen, Inc. today reported that its anti-cancer product, the anti-CD55 antibody, was found to significantly enhance the activity of Rituxan® when both drugs were used together in a cell-based evaluation study. The anti-CD55 antibody is under an exclusive option from Cancer Research Technology (U.K.), and is being developed for the treatment of a broad range of solid tumors. These preliminary results indicate its potential in improving the efficacy of leading cancer therapies.

Previous laboratory studies confirmed that the anti-CD55 antibody binds to a specific target expressed on the surface of tumor cells and removes one of the tumor's most important protective mechanisms, thereby making cancer cells vulnerable to attack by the immune system or other anti-cancer products. In this in vitro study, the antibody was combined with Rituxan® (Rituximab), a leading cancer medication with global sales of more than $1.5 billion in 2004 that is jointly marketed by Biogen Idec, Inc. and Genentech, Inc.

The results showed that the combination of the anti-CD55 antibody and Rituxan® led to a significant increase in the destruction of cancer cells as compared to Rituxan® alone. The study was conducted by researchers at Viragen (Scotland) Ltd.

Karen Jervis, Ph.D., Viragen's Director of Product Development, explained, "There is much published data suggesting that the efficacy of many therapeutic products, including monoclonal antibodies, may be limited by the presence of certain proteins on tumor surfaces that protect the tumor from attack by the immune system. One of these proteins is CD55, which is expressed on most tumor cells at far higher levels than on normal cells, and its function helps prevent the destruction of tumor cells. We have developed a unique anti-CD55 antibody that effectively removes this protective effect.

"We have previously demonstrated that the anti-CD55 antibody binds to the CD55 protein on the tumor cell's surface with great specificity and deactivates its defense," she continued. "Our new results using the antibody in tandem with Rituxan® are very encouraging as they demonstrate the synergistic effect of 'anti-CD55' when combined with a proven antibody in vitro. We believe this same beneficial effect may also be realized when we use the antibody with other cancer products, and we hope to yield similar results with other commercial anti-cancer agents."

The development of the antibody has been funded in part by an $833,000 grant awarded to Viragen (Scotland) Ltd. from the Scottish Government (Scottish Executive) in April 2004, and Viragen scientists continue to design and conduct preclinical studies in support of this program.

Viragen undertook this study initiative on its own behalf to determine the potential effects of co-therapy with the anti-CD55 antibody. Viragen has no agreements with Biogen Idec, Inc. or Genentech, Inc., and did not collaborate with either company in connection with the study. The anti-CD55 antibody is not approved for sale in any market or territory, and human clinical trials will be required prior to seeking approval from any international regulatory agency.

Further Information

Anti-CD55 Antibody Project:

The University of Nottingham (England) and Viragen are developing the anti-CD55 antibody to block the protective effect of the protein CD55 on the surface of tumor cells. The protein CD55 is one of a number of proteins that protect normal healthy cells from being destroyed by the complement system, part of the human immune response against disease. The problem arises when cancer cells also express this control protein at high levels to camouflage and protect the cancerous cells from the immune system.

The anti-CD55 antibody acts to remove the tumor's protective mechanism and is expected to boost patient response rates either as a stand-alone therapy or in combination with other antibodies. Viragen holds an option from Cancer Research Technology Limited to acquire an exclusive worldwide license to this technology with potential application in a number of cancer types.

About Rituxan® :

In November 1997, Rituxan® became the first monoclonal antibody to be approved by the U.S. Food and Drug Administration for a cancer indication, and today it is the #1 seller of cancer therapeutics in the United States. Rituxan® is indicated for the treatment of patients with relapsed or refractory, low grade or follicular, CD20-positive, B-cell non-Hodgkin's lymphoma (NHL), which is a cancer of the lymphatic system. Physicians are exploring the use of Rituxan® in a wide variety of settings including the treatment of other forms of NHL and CLL (chronic lymphocytic leukemia), as both frontline therapy and treatment for relapsed patients, in combination with other oncologic agents, and to induce as well as maintain remissions. Additionally, clinical trials have been initiated with Rituxan® in other B-cell malignancies such as multiple myeloma, as well as non-malignant conditions such as rheumatoid arthritis and lymphoproliferative disorders associated with solid organ transplant therapies.

Rituxan® , discovered by IDEC, is approved for sale in approximately 70 countries worldwide. Biogen Idec co-promotes Rituxan® in the U.S. with Genentech, Inc. Biogen Idec shares responsibility with Genentech for the sale and continued development of Rituxan® in the U.S. F. Hoffmann-La Roche Ltd. of Switzerland has marketing rights to Rituxan® outside of the U.S., and co- promotes Rituxan® in Japan with Zenyaku Kogyo Col. Ltd. of Japan.

From Biogen Idec, Inc: http://www.biogen.com/

About Cancer Research Technology Limited:

Cancer Research Technology Limited (CRT) is a specialist technology transfer and development company that aims to develop new discoveries in cancer research for the benefit of cancer patients. CRT is wholly owned by Cancer Research U.K., the largest independent funder of cancer research in the world. CRT works closely with leading international cancer scientists and their institutes to protect intellectual property arising from their research and to establish links with commercial partners. CRT facilitates the discovery, development and marketing of new cancer therapeutics, vaccines, diagnostics and enabling technologies.

About Viragen, Inc.:

Viragen is a biotechnology company specializing in the research, development and commercialization of natural and recombinant protein-based drugs designed to treat a broad range of viral and malignant diseases. These protein-based drugs include Multiferon ® (natural human alpha interferon), monoclonal antibodies and a peptide drug. Viragen's strategy also includes the development of Avian Transgenic Technology as a biomanufacturing platform for the large-scale, cost-effective production of therapeutic proteins.

Viragen is publicly traded on the American Stock Exchange (VRA). Viragen's majority owned subsidiary, Viragen International, Inc., is publicly traded on the Over-The-Counter Bulletin Board (VGNI). Viragen's key partners and licensors include: Roslin Institute, Memorial Sloan-Kettering Cancer Center, Cancer Research UK, University of Nottingham (U.K.), University of Miami, America's Blood Centers and the German Red Cross.

For more information, please visit: http://www.viragen.com/ Viragen, Inc. Corporate Contact: Douglas Calder, Director of Communications Phone: (954) 233-8746; Fax: (954) 233-1414 E-mail: dcalder@viragen.com

The foregoing press announcement contains forward-looking statements that can be identified by such terminology such as "expect," "potential," "suggests," "may," "should," "could" or similar expressions. Such forward- looking statements involve known and unknown risks, uncertainties and other factors that may cause the actual results to be materially different from any future results, performance or achievements expressed or implied by such statements. In particular, management's expectations regarding future research, development and/or commercial results could be affected by, among other things, uncertainties relating to clinical trials and product development; availability of future financing; unexpected regulatory delays or government regulation generally; the Company's ability to obtain or maintain patent and other proprietary intellectual property protection; and competition in general. Forward-looking statements speak only as to the date they are made. The Company does not undertake to update forward-looking statements to reflect circumstances or events that occur after the date the forward-looking statements are made.

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